Browse Prior Art Database

Microcontroller Instruction Execute Diagnostic Procedure

IP.com Disclosure Number: IPCOM000086126D
Original Publication Date: 1976-Jul-01
Included in the Prior Art Database: 2005-Mar-03
Document File: 2 page(s) / 74K

Publishing Venue

IBM

Related People

Dumstorff, EF: AUTHOR [+3]

Abstract

This procedure reduces and simplifies microcode required for field replaceable unit (FRU) isolation in a device dependent adapter, connected to an input/output controller (IOC) of a computer system. The procedure allows a program (PR) executed by the central processing unit (CPU) of the computer system to set up and issue a diagnostic command to a microcontroller in the IOC, which will execute a read-only storage (ROS) instruction sequence determined by parameters supplied with the diagnostic command. The PR also specifies all operand data for the sequence.

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Microcontroller Instruction Execute Diagnostic Procedure

This procedure reduces and simplifies microcode required for field replaceable unit (FRU) isolation in a device dependent adapter, connected to an input/output controller (IOC) of a computer system. The procedure allows a program (PR) executed by the central processing unit (CPU) of the computer system to set up and issue a diagnostic command to a microcontroller in the IOC, which will execute a read-only storage (ROS) instruction sequence determined by parameters supplied with the diagnostic command. The PR also specifies all operand data for the sequence.

The sequence can be anywhere in the normal ROS code, therefore, not requiring special diagnostic code. After the sequence has been executed, the PR verifies the proper results by reading the appropriate register and data store locations and compares these with predicted results. The results of the comparison aid in FRU isolation.

The drawing shows the order of events and the relationship of the microcontroller, the PR and a second microcontroller (SM). The SM is also part of the computer system and interacts with the PR and the first microcontroller as shown. This procedure enables diagnostic tests for the IOC device dependent adapter and the device connected to be controlled by the adapter, to use normal run or control code for FRU isolation. Thus the additional diagnostic code is minimal and can be separate from the run code for common use by several a...